wireguard-linux/tools/objtool, branch stable

objtool: Fix skip_alt_group() for non-alternative STAC/CLAC

2025-11-01T06:43:20Z

If an insn->alt points to a STAC/CLAC instruction, skip_alt_group() assumes it's part of an alternative ("alt group") as opposed to some other kind of "alt" such as an exception fixup. While that assumption may hold true in the current code base, Linus has an out-of-tree patch which breaks that assumption by replacing the STAC/CLAC alternatives with raw STAC/CLAC instructions. Make skip_alt_group() more robust by making sure it's actually an alt group before continuing. Reported-by: Linus Torvalds Fixes: 2d12c6fb7875 ("objtool: Remove ANNOTATE_IGNORE_ALTERNATIVE from CLAC/STAC") Closes: https://lore.kernel.org/CAHk-=wi6goUT36sR8GE47_P-aVrd5g38=VTRHpktWARbyE-0ow@mail.gmail.com Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Tested-by: Linus Torvalds Link: https://patch.msgid.link/3d22415f7b8e06a64e0873b21f48389290eeaa49.1761767616.git.jpoimboe@kernel.org

objtool: Fix failure when being compiled on x32 system

2025-10-22T13:21:55Z

Fix compilation failure when compiling the kernel with the x32 toolchain. In file included from check.c:16: check.c: In function ¡check_abs_references¢: /usr/src/git/linux-2.6/tools/objtool/include/objtool/warn.h:47:17: error: format ¡%lx¢ expects argument of type ¡long unsigned int¢, but argument 7 has type ¡u64¢ {aka ¡long long unsigned int¢} [-Werror=format=] 47 | "%s%s%s: objtool" extra ": " format "\n", \ | ^~~~~~~~~~~~~~~~~ /usr/src/git/linux-2.6/tools/objtool/include/objtool/warn.h:54:9: note: in expansion of macro ¡___WARN¢ 54 | ___WARN(severity, "", format, ##__VA_ARGS__) | ^~~~~~~ /usr/src/git/linux-2.6/tools/objtool/include/objtool/warn.h:74:27: note: in expansion of macro ¡__WARN¢ 74 | #define WARN(format, ...) __WARN(WARN_STR, format, ##__VA_ARGS__) | ^~~~~~ check.c:4713:33: note: in expansion of macro ¡WARN¢ 4713 | WARN("section %s has absolute relocation at offset 0x%lx", | ^~~~ Fixes: 0d6e4563fc03 ("objtool: Add action to check for absence of absolute relocations") Signed-off-by: Mikulas Patocka Signed-off-by: Peter Zijlstra (Intel) Acked-by: Ard Biesheuvel Link: https://patch.msgid.link/1ac32fff-2e67-5155-f570-69aad5bf5412@redhat.com

objtool/rust: add one more `noreturn` Rust function

2025-10-22T13:21:54Z

Between Rust 1.79 and 1.86, under `CONFIG_RUST_KERNEL_DOCTESTS=y`, `objtool` may report: rust/doctests_kernel_generated.o: warning: objtool: rust_doctest_kernel_alloc_kbox_rs_13() falls through to next function rust_doctest_kernel_alloc_kvec_rs_0() (as well as in rust_doctest_kernel_alloc_kvec_rs_0) due to calls to the `noreturn` symbol: core::option::expect_failed from code added in commits 779db37373a3 ("rust: alloc: kvec: implement AsPageIter for VVec") and 671618432f46 ("rust: alloc: kbox: implement AsPageIter for VBox"). Thus add the mangled one to the list so that `objtool` knows it is actually `noreturn`. This can be reproduced as well in other versions by tweaking the code, such as the latest stable Rust (1.90.0). Stable does not have code that triggers this, but it could have it in the future. Downstream forks could too. Thus tag it for backport. See commit 56d680dd23c3 ("objtool/rust: list `noreturn` Rust functions") for more details. Signed-off-by: Miguel Ojeda Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Alice Ryhl Cc: stable@vger.kernel.org # Needed in 6.12.y and later. Link: https://patch.msgid.link/20251020020714.2511718-1-ojeda@kernel.org

Merge tag 'x86_core_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-10-11T18:19:16Z

Pull more x86 updates from Borislav Petkov: - Remove a bunch of asm implementing condition flags testing in KVM's emulator in favor of int3_emulate_jcc() which is written in C - Replace KVM fastops with C-based stubs which avoids problems with the fastop infra related to latter not adhering to the C ABI due to their special calling convention and, more importantly, bypassing compiler control-flow integrity checking because they're written in asm - Remove wrongly used static branches and other ugliness accumulated over time in hyperv's hypercall implementation with a proper static function call to the correct hypervisor call variant - Add some fixes and modifications to allow running FRED-enabled kernels in KVM even on non-FRED hardware - Add kCFI improvements like validating indirect calls and prepare for enabling kCFI with GCC. Add cmdline params documentation and other code cleanups - Use the single-byte 0xd6 insn as the official #UD single-byte undefined opcode instruction as agreed upon by both x86 vendors - Other smaller cleanups and touchups all over the place * tag 'x86_core_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86,retpoline: Optimize patch_retpoline() x86,ibt: Use UDB instead of 0xEA x86/cfi: Remove __noinitretpoline and __noretpoline x86/cfi: Add "debug" option to "cfi=" bootparam x86/cfi: Standardize on common "CFI:" prefix for CFI reports x86/cfi: Document the "cfi=" bootparam options x86/traps: Clarify KCFI instruction layout compiler_types.h: Move __nocfi out of compiler-specific header objtool: Validate kCFI calls x86/fred: KVM: VMX: Always use FRED for IRQs when CONFIG_X86_FRED=y x86/fred: Play nice with invoking asm_fred_entry_from_kvm() on non-FRED hardware x86/fred: Install system vector handlers even if FRED isn't fully enabled x86/hyperv: Use direct call to hypercall-page x86/hyperv: Clean up hv_do_hypercall() KVM: x86: Remove fastops KVM: x86: Convert em_salc() to C KVM: x86: Introduce EM_ASM_3WCL KVM: x86: Introduce EM_ASM_1SRC2 KVM: x86: Introduce EM_ASM_2CL KVM: x86: Introduce EM_ASM_2W ...

Merge tag 'kbuild-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux

2025-10-02T03:58:51Z

Pull Kbuild updates from Nathan Chancellor: - Extend modules.builtin.modinfo to include module aliases from MODULE_DEVICE_TABLE for builtin modules so that userspace tools (such as kmod) can verify that a particular module alias will be handled by a builtin module - Bump the minimum version of LLVM for building the kernel to 15.0.0 - Upgrade several userspace API checks in headers_check.pl to errors - Unify and consolidate CONFIG_WERROR / W=e handling - Turn assembler and linker warnings into errors with CONFIG_WERROR / W=e - Respect CONFIG_WERROR / W=e when building userspace programs (userprogs) - Enable -Werror unconditionally when building host programs (hostprogs) - Support copy_file_range() and data segment alignment in gen_init_cpio to improve performance on filesystems that support reflinks such as btrfs and XFS - Miscellaneous small changes to scripts and configuration files * tag 'kbuild-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (47 commits) modpost: Initialize builtin_modname to stop SIGSEGVs Documentation: kbuild: note CONFIG_DEBUG_EFI in reproducible builds kbuild: vmlinux.unstripped should always depend on .vmlinux.export.o modpost: Create modalias for builtin modules modpost: Add modname to mod_device_table alias scsi: Always define blogic_pci_tbl structure kbuild: extract modules.builtin.modinfo from vmlinux.unstripped kbuild: keep .modinfo section in vmlinux.unstripped kbuild: always create intermediate vmlinux.unstripped s390: vmlinux.lds.S: Reorder sections KMSAN: Remove tautological checks objtool: Drop noinstr hack for KCSAN_WEAK_MEMORY lib/Kconfig.debug: Drop CLANG_VERSION check from DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT riscv: Remove ld.lld version checks from many TOOLCHAIN_HAS configs riscv: Unconditionally use linker relaxation riscv: Remove version check for LTO_CLANG selects powerpc: Drop unnecessary initializations in __copy_inst_from_kernel_nofault() mips: Unconditionally select ARCH_HAS_CURRENT_STACK_POINTER arm64: Remove tautological LLVM Kconfig conditions ARM: Clean up definition of ARM_HAS_GROUP_RELOCS ...

Merge tag 'x86_apic_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-09-30T20:40:35Z

Pull x86 SEV and apic updates from Borislav Petkov: - Add functionality to provide runtime firmware updates for the non-x86 parts of an AMD platform like the security processor (ASP) firmware, modules etc, for example. The intent being that these updates are interim, live fixups before a proper BIOS update can be attempted - Add guest support for AMD's Secure AVIC feature which gives encrypted guests the needed protection against a malicious hypervisor generating unexpected interrupts and injecting them into such guest, thus interfering with its operation in an unexpected and negative manner. The advantage of this scheme is that the guest determines which interrupts and when to accept them vs leaving that to the benevolence (or not) of the hypervisor - Strictly separate the startup code from the rest of the kernel where former is executed from the initial 1:1 mapping of memory. The problem was that the toolchain-generated version of the code was being executed from a different mapping of memory than what was "assumed" during code generation, needing an ever-growing pile of fixups for absolute memory references which are invalid in the early, 1:1 memory mapping during boot. The major advantage of this is that there's no need to check the 1:1 mapping portion of the code for absolute relocations anymore and get rid of the RIP_REL_REF() macro sprinkling all over the place. For more info, see Ard's very detailed writeup on this [1] - The usual cleanups and fixes Link: https://lore.kernel.org/r/CAMj1kXEzKEuePEiHB%2BHxvfQbFz0sTiHdn4B%2B%2BzVBJ2mhkPkQ4Q@mail.gmail.com [1] * tag 'x86_apic_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (49 commits) x86/boot: Drop erroneous __init annotation from early_set_pages_state() crypto: ccp - Add AMD Seamless Firmware Servicing (SFS) driver crypto: ccp - Add new HV-Fixed page allocation/free API x86/sev: Add new dump_rmp parameter to snp_leak_pages() API x86/startup/sev: Document the CPUID flow in the boot #VC handler objtool: Ignore __pi___cfi_ prefixed symbols x86/sev: Zap snp_abort() x86/apic/savic: Do not use snp_abort() x86/boot: Get rid of the .head.text section x86/boot: Move startup code out of __head section efistub/x86: Remap inittext read-execute when needed x86/boot: Create a confined code area for startup code x86/kbuild: Incorporate boot/startup/ via Kbuild makefile x86/boot: Revert "Reject absolute references in .head.text" x86/boot: Check startup code for absence of absolute relocations objtool: Add action to check for absence of absolute relocations x86/sev: Export startup routines for later use x86/sev: Move __sev_[get|put]_ghcb() into separate noinstr object x86/sev: Provide PIC aliases for SEV related data objects x86/boot: Provide PIC aliases for 5-level paging related constants ...

Merge 6.17-rc6 into kbuild-next

2025-09-19T20:43:11Z

Commit bd7c2312128e ("pinctrl: meson: Fix typo in device table macro") is needed in kbuild-next to avoid a build error with a future change. While at it, address the conflict between commit 41f9049cff32 ("riscv: Only allow LTO with CMODEL_MEDANY") and commit 6578a1ff6aa4 ("riscv: Remove version check for LTO_CLANG selects"), as reported by Stephen Rothwell [1]. Link: https://lore.kernel.org/20250908134913.68778b7b@canb.auug.org.au/ [1] Signed-off-by: Nathan Chancellor

objtool/LoongArch: Mark special atomic instruction as INSN_BUG type

2025-09-18T11:43:36Z

When compiling with LLVM and CONFIG_RUST is set, there exists the following objtool warning: rust/compiler_builtins.o: warning: objtool: __rust__unordsf2(): unexpected end of section .text.unlikely. objdump shows that the end of section .text.unlikely is an atomic instruction: amswap.w $zero, $ra, $zero According to the LoongArch Reference Manual, if the amswap.w atomic memory access instruction has the same register number as rd and rj, the execution will trigger an Instruction Non-defined Exception, so mark the above instruction as INSN_BUG type to fix the warning. Cc: stable@vger.kernel.org Signed-off-by: Tiezhu Yang Signed-off-by: Huacai Chen

objtool/LoongArch: Mark types based on break immediate code

2025-09-18T11:43:36Z

If the break immediate code is 0, it should mark the type as INSN_TRAP. If the break immediate code is 1, it should mark the type as INSN_BUG. While at it, format the code style and add the code comment for nop. Cc: stable@vger.kernel.org Suggested-by: WANG Rui Signed-off-by: Tiezhu Yang Signed-off-by: Huacai Chen

objtool: Ignore pi_cfi_ prefixed symbols

2025-09-09T10:02:01Z

When building with CONFIG_CFI_CLANG=y after the recent series to separate the x86 startup code, there are objtool warnings along the lines of: vmlinux.o: warning: objtool: __pi___cfi_startup_64_load_idt() falls through to next function __pi_startup_64_load_idt() vmlinux.o: warning: objtool: __pi___cfi_startup_64_setup_gdt_idt() falls through to next function __pi_startup_64_setup_gdt_idt() vmlinux.o: warning: objtool: __pi___cfi___startup_64() falls through to next function __pi___startup_64() As the comment in validate_branch() states, this is expected, so ignore these symbols in the same way that __cfi_ and __pfx_ symbols are already ignored for the rest of the kernel. Fixes: 7b38dec3c5af ("x86/boot: Create a confined code area for startup code") Signed-off-by: Nathan Chancellor Signed-off-by: Borislav Petkov (AMD) Acked-by: Ard Biesheuvel